<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Upload UML Diagram</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css">
</head>
<body>
<div class="container mt-5">
<h1 class="text-center">Upload UML Diagram</h1>
<form action="/upload" method="post" enctype="multipart/form-data">
<div class="form-group">
<label for="file">Choose UML diagram image</label>
<input type="file" class="form-control-file" id="file" name="file" required>
</div>
<button type="submit" class="btn btn-primary">Upload</button>
</form>
</div>
</body>
</html>